I started out buying a used Harbor Freight manual tire changer, I mounted it to a large pallet since I didn't really want to bolt it to the floor.
It did the job, but agreed it was a little flimsy.

The next step was a used Coats 40/40 tire machine I got used, I traded a used garden tiller for it.
It worked great, but you're limited to 17 inch wheels max.

I was given an old Hunter 700 Spin Balancer at one point, it worked but it had to lift the wheel and tire up because it had a vertical shaft.
Poor design IMO, but it was an early spin balancer (70's era).

Now I have a rim clamp tire machine, I wanted one that would clamp 20 inch wheels on the outside.
I bought it along with a spin balancer (combo deal).

Each style of tire machine has it's good and bad points.